The present application relates to a coordinate detection apparatus and a display apparatus that detect a position coordinate of a detection target in accordance with changes in capacitance.
In recent years, there has been widespread usage of electronic apparatuses that detect a position of a finger in accordance with changes in capacitance and control screen display and apparatus operation. This kind of capacitance sensors generally determine an input position in accordance with contact or proximity of a finger in a flat plane by detecting changes in capacitance of a plurality of electrodes arranged in the flat plane.
For example, Japanese Patent Application Laid-open No. 2008-269297 (hereinafter, referred to as Patent Document 1) describes a coordinate input device including a pair of detection electrodes including one detection electrode and the other detection electrode that have the same outer shape. Each of the detection electrodes has an approximate right-angled triangular shape, which is flat. The detection electrodes are arranged such that the sides of the respective detection electrodes are opposed to each other, so that the width of the one detection electrode narrows toward a first direction and the width of the other detection electrode widens toward the first direction. A plurality of pairs of detection electrodes are arranged in a second direction orthogonal to the first direction, and the coordinate input device detects coordinates of an input position in accordance with changes in capacitance of the detection electrodes.
In particular, the coordinate input device is configured to calculate coordinates of an input position along the first direction in accordance with a ratio (ΣCL/ΣCR) of a total sum (ΣCL) of amounts of changes in capacitance of the one detection electrodes to a total sum (ΣCR) of amounts of changes in capacitance of the other detection electrodes.